If Turbo Tax told you that you needed to mail something it was probably the whole 1040 tax return and W2s.  

Did you go all the way through the File tab, through the 3 steps and hit the big orange Transmit Returns Now button?

You can check your efile status here     

https://turbotax.intuit.com/tax-tools/efile-status-lookup/   

When you efile you get back 2 emails.  The first email only confirms the transmission.  The second email says if the IRS (or state) Accepted or Rejected your efile.

When you log into your account you should also see the status and if it was Accepted or Rejected, Started, Printed, Ready to Mail, etc.  What does it say?

It says “Ready to Mail”

On the top of the page it says “ready to mail” and I click see all my returns and it sends me to the bottom of the page to and it says “return status: Printed”

So did you actually print out and mail your return to the IRS yourself?  You should always get a tracking number from the Post Office so you know that they get it.  

Ready to Mail means you have to actually print out your tax return and mail it to the IRS yourself. So it has not been filed yet. And it will always say Ready to Mail. Turbo Tax doesn’t know if or when you mailed it and the IRS doesn’t update Turbo Tax when they get your mailed return. You can try to switch to efile
https://ttlc.intuit.com/community/e-file/help/how-do-i-change-from-mail-to-e-file-in-turbotax-online...

When you mail a tax return, you need to attach any documents showing tax withheld, such as your W-2’s or any 1099’s. Use a mailing service that will track it, such as UPS or certified mail so you will know the IRS received the return. Don’t forget state.

Important! Mail Federal and State in separate envelopes and mail each year in separate envelopes.